Manufacture of peg-lamps



J, DA'L-ZBL'L'. Manufacture of Peg-Lamps, No. 224,519. Patented-Feb, 17, 1880.

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N4 PETERS, PIIOTO-LITHOGRAFHER, WASHINGTON. D O,

UNITED STATES;

JAMES nALzELnoF PITTSBURG, PENNSYLVANIA. I

MANUFACTURE oF PEG-LAMPS.

SPECIFICATION formingpart of Letters Patent No. 224,519, dated February 17, 1880. Application filed. December 2,1879. 1

To all whom it may concern:

Be it known that I, JAMES DALZELL, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in the Manufacture of Peg-Lamps; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being bad to the accompanying drawing, which forms a part of this specification, and which is a side view of my improved peg-lamp still in the mold in which it was formed, one half of the mold being removed.

Peg-lamps are lamps having a short stem or peg formed on the lower side for the pure pose of attachment to the stand, base, or bracket upon which they are placed. The usual method of making them is to place a solid lump of glass in a cavity in the bottom of the mold and to blow the bowl upon it. The union thus formed is imperfect, and there is a difference in the contraction and expansion of the broad thin lamp-bowl and the thick narrow peg or lump, which causes frequent breaking or fracture at that point. This breaking or flying may occur at any moment, and is the cause of excessive loss.

Iron pegs have been substituted for glass to some extent, the bowl being blown onto them; but they have been found to be subject to the same breakage arising from the same cause.

My invention consists of forming the peg of a thin metal tube and casting the bowl into it.

To enable others skilled in the art 'to make,

use of my invention, I will describe its construction and the method and moldfor making it.

I take an ordinary two or more part mold, a, for making lamp-bowls and form in the center of the bottom a cylindrical cavity, b, in which I place a short round piece of metal, 0, of slightly less diameter than'that of the cavity b, and not so long. I also place in the cavity, between the piece 0 and the sides of the cavity, a short tube, 0?, of tin, brass, or other suitable material, the upper end of which is contracted slightlyby drawing in the edges. This tube is preferably longer than the'cavity and projects from it, but may be shorter. The lamp-bowl is blown in the usual way,

end of the tube, which is embedded in the lower side of the bowl. Thus the tube is firmly and permanently secured to the lamp. The glass which enters its upper end, being part of the bowl itself, does not have, if any, an injuriously different degree of expansion and contraction from that of the bowl itself, and the whole structure is much stronger than the lamp-bowls of the prior forms mentioned, as there is no joint between the parts, which such expansion and contraction would tend to rupture. Thelower end of the tube must be open, as shown,'or perforated, to permit the escape of the air therefrom. If it had no provision of this kind, the air would be confined in it and would prevent the molten glass from entering. A

By the construction-shown I obtain a socket, e, in the bottom of the peg, by which I can attach it to the stem of the stand.

In using the open-ended tube 11, I make use of the plug 0 in themold; but-instead of it I can place a perforated diaphragm or piece of tin in the tube at the required distance from the end to limit the downward flow of the glass, or I can draw in or contract the tube in the middle sufficiently for that purpose. When the lamp is removed from the mold the plug 0 remains for further use. This plug may be made solid with or attached to the mold.

Instead of drawing in the upper end of the tube d, to aiford a hold for the glass, loan indent it externally to produce internal projections, or I can make an annular groove around it, or I canimpress a screw-thread on it. In all these cases the glass will take a suitable hold in the tube. Any irregularity, projec- ..tion,'or recess which will permit it to do so will answer. 7

The tube may be of any ornamental design, and may be threaded throughout its length, and then it will make a screw-fastening with the stand, base, or bracket. It may have a closed lower end if there are holes orpunctures for the escape of the air.

Thismethodmaybeused with other stemmed 2. A glass-mold having a cylindrical cavity articles of glassware, and with pressed as well extending from the main cavity, in combinaas blown ware. It enables me to obtain a tion with a solid plug or piece placed therein cheap, permanent, and ornamental fastening. to stay the downward flow of the glass in the 15 5 What I claim as my invention, and desire to hollow peg, substantially as described.

secure by Letters Patent, is- In testimony whereof I, the said JAMES 1. A peg-lamp or other article of glassware DALZELL, have hereunto set my hand. cast to a hollow metallic peg which projects JAMES DALZELL. beyond and is closed by the glass side of the Witnesses: 10 article, substantially as and for/file purposes JAMES H. PORTE,

described. '1. B. KERR. 

